It seems, that docs are outdated.
Default data alignment in records is expected to be wordly (i386, win32).
But if a record has int64 (or qword) element, I get unexpected overheads.
It's easily avoidable (with {$PACKRECORDS 1} or {$A1}; even with {$A-} [which
is expected to work only on MAC, according to docs]), but unexpected.
type
a= record
a: longword;
b: longword;
c: longword;
end; // 12 expected
b= record
ab: int64;
c: longword;
end; // 12 expected
c= record
ab: array[0..7] of byte;
c: byte; // 1b overhead expected
d: word;
e: byte; // 1b overhead expected
end; // 14 expected
d= record
ab: int64;
c: byte; // 1b overhead expected
d: word;
e: byte; // 1b overhead expected
end; // 14 expected
e= record
a: byte;
b: byte;
c: word;
d: longword;
e: word;
f: byte;
g: byte;
end; // well, 12 expected
begin
writeln(sizeof(a)); // 12 ok!
writeln(sizeof(b)); // 16 ???
writeln(sizeof(c)); // 14 ok!
writeln(sizeof(d)); // 16 ???
writeln(sizeof(e)); // 12 ok!
end. // I don't know the numbers on other platforms/systems
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